Glaze breaker



Get. 10, 1933. R w HAMlLTON 1,929,888

GLAZE BREAKER Filed Jan. 26, 1931 INVENTOR P0667 2 WHam i/fo/z/ BY H\$ ATTOR? Patented Oct. 10, 1933 UNITED STATES PATENT! OFFICE Application January 26,

2 Claims.

This invention relates to glaze breakers and more particularly to a glaze breaker for valve seats of internal combustion engines.

Among the principal objects which the invention has in view are: To provide an improved tool for breaking the glaze or crystalized carbon coating on valve seats; to provide a tool which will be readily adapted to different diameters of valve seats; to enable the glaze to be removed evenly and entirely and without injury to the valve seat; to enable the device to be readily operated; to avoid the need of constantly cleaning the tool; to secure simplicity of construction and operation; and to obtain other advantages and results as may be brought out in the following description.

In the drawing:

Figure 1 is a plan of the tool showing the same in operative position on a valve seat;

Figure 2 is a sectional view of the valve seat 2() showing the tool applied in elevation thereto; and

Figure 3 is an elevation of the tool looking at the right side of Figure 2.

In the specific embodiment of the invention illustrated in said drawing, the reference numeral 10 indicates a portion of an internal combustion engine, and showing particularly a valve seat 11 and guide bushing 12 for the valve-stem (not shown). This portion of the engine represents the work upon which my invention is to operate,

but it is to be understood that other work than the specific one shown and mentioned may be advantageously treated.

As shown in the drawing, the invention comprises in its general aspects a stem 13, a lower portion or member 14 of which is cylindrical and preferably of an appropriate size to be introduced into the guide-bushing 12 of the work. An upper portion or head 15 of the stem supports a transverse stud 16 at an outer portion or end of which is carried an abrasive member 17. By this construction, rotation of the stem 13 will gyrate the abrasive member about the axis of the stem. The parts are so proportioned and arranged that the abrasive member 17 will gyrate in contact with the work and perform the desired operation thereon while being so gyrated.

Describing the parts in greater detail, it may be observed that the cylindrical portion or member 14 of stem 13 is received at its upper end in a suitable'socket 18 in the lower end of the upper portion or head 15. These two parts of the stem are held together as a unit by suitable means, such as a cotter-pin 19 extending transversely through the overlapping portions of said parts. By this construction a different cylindrical mem- 1931. Serial No. 511,243

ber 14 may be substituted as may be required for different pieces of work. The upper portion or head 15 of the stem preferably has an angular cross-section, for instance, square as shown, so that a wrench or other tool may be applied thereto for imparting a rotary motion thereto. It is furthermore desirable that the upper end of the head 15 be above the level of the abrasive member 17 so that the actuating tool may be readily applied to the head from any side thereof.

In order that the abrasive member 17 may be properly addressed to work, or valve seats of different diameters, said member is by preference made adjustable with respect to the supporting and rotating stem. As one convenient manner of accomplishing this desideratum, stud 16 is externally screw-threaded at its end passing through the stem head 15, and the hole through which it passes is correspondingly threaded. A look nut 20 applied at the projecting end of the stud and brought home against the stem head will maintain the stud at its adjusted position until manually changed. On the opposite side of the head 15 from the lock nut, the stud is preferably provided with an external or annular shoulder 21 and beyond that shoulder the stud is likewise threaded so as to receive another lock nut 22 for clamping the abrasive member against said shoulder. A washer 23 is shown between this clamping nut 22 and the abrasive member 17 so as to avoid injury to said member when the nut is tightened. It may be observed in this connection, that when the stud is locked to the stem and when the abrasive member is locked to the stud, the abrasive member cannot rotate about its own axis or the axis of the stud, but is fixed with respect thereto, and its movement with respect to the work is one of gyrating about the axis of the stem as the stem is rotated.

The abrasive member 1'7 is shown as circular, such being the preferred shape, the peripheral edge having a bevel 24 corresponding to the usual bevel of a valve seat. The provision of the circular abrasive member enables the toolto be adjusted readily to the proper extended position of the abrasive member with respect to the stem without having to make another adjustment to align the abrasive member. It also enables the abrasive member to be used for a long time without cleaning, as it may be turned to an unused part of the surface when the part being used becomes clogged or otherwise adversely affected. The circular configuration of the abrasive member furthermore is one which lends itself readily to being cleaned or ground down when the sur- 10 face becomes clogged or otherwise undesirable for further use. The tool will therefore have a long life and will be universal in use upon different pieces or sizes of work.

What is claimed,

1. In a device as characterized comprising in combination with a rotatable stem having a square head, a stud transversely supported by said stem, a circular abrasive member mounted adjacent one end of said stud, a pair of lock nuts on said stud, one of said lock nuts adapted to lock the stud against the stem head in adjusted position, the other said lock nut being adapted to clamp the abrasive member to the stud and hold the same from rotating about its own axis when the said device is in operation.

2. In a device as characterized comprising in combination with a rotatable stem having a square head, a stud transversely supported by said stem, a circular abrasive member mounted adjacent one end of said stud, a lock nut for securing the stud to the stem in adjusted position, a washer mounted on the stud and adjacent one side of the said circular abrasive member, and a second lock nut adapted to clamp said washer against the abrasive member whereby with said Washer in locked position prevents rotation of the said abrasive member about its own axis when the said device is in operation.

ROBERT W. HAMILTON. 

